Is there an enforceable contract between Nal and Monalisa? explain why

Nal is the year 12 Arts teacher responsible for organising the end of year school Arts production show. This year Nal wishes to present her own Arts play - 'Little Cinderella'. Nal is responsible for all aspects of the production including costuming, catering and set up. She has been encouraged to access volunteer resources where possible - including the schools 'Parents and Friends Association'. Nal only has 1 month to get it all organised. Nal is aware of a 16-year-old year 10 student - Monalisa - who has set up her own catering from home project - preparing cakes and sandwiches for school events. Nal speaks to Monalisa after class and asks whether she can prepare cakes and sandwiches for 200 people. Monalisa says yes, I can - I will need one week's' notice and it will be $20 per person - $4000 in total". Nal says, 'I will need to think about it for a day or two.' Monalisa says, 'send me a Facebook message if you want me to proceed - I have a Facebook website 'Monalisa Fast Food Catering' where I take all our orders'. Later that week Nal sends a text message to Monalisa that says, 'go ahead with the cakes and sandwiches as we discussed'.